class Headline extends DataObject {
   static $db = array(
      'Title' => 'Varchar',
      'Text' => 'HTMLText',
   );

   static $has_one = array(
      'Image' => 'Image',
   );

   static $belongs_many_many = array(
      'Pages' => 'Page'
   );

   function getThumbnail() {
      $Image = $this->Image();
      if ($Image) {
         return $Image->CMSThumbnail();
      }
      else {
         return null;
      }
   }

   function getCMSFields_forPopup() {
      $fields = new FieldSet();
      $fields->push(new TextField('Title'));
      $textField = new SimpleTinyMCEField('Text', 'Text', array(), 3);
      $textField->setButtons(array(
         'bold,italic,underline,|,link,unlink,anchor'
      ));
      $fields->push($textField);
      $fields->push(new ImageField('Image'));
      
      return $fields;
   }

}

class Page extends SiteTree {
   static $db = array(
   );
   
   static $has_one = array(
   );

   static $many_many = array(
      'Headlines' => 'Headline'
   );
   
   function getCMSFields() {
      $fields = parent::getCMSFields();

      // headlines tab
      $headlinesTableField = new ManyManyDataObjectManager(
         $this,
         'Headlines',
         'Headline',
         array(
            'Title' => 'Title',
            'Text' => 'Text',
            'Thumbnail' => 'Image',
         ),
         'getCMSFields_forPopup'
      );
      $headlinesTableField->setAddTitle('a Headline');

      $fields->addFieldToTab('Root.Content.Headlines', $headlinesTableField);

      return $fields;
   }

}